The time-dependent behavior of macromolecules binding to receptors immobilized within a polymer matrix was explored via computer simulation. The literature on determination of the chemical kinetics using biosensor instrumentation has been reviewed in light of the results obtained in the simulations. Development of an automated technique for the quantitative determination of unprecedentedly small amounts of unlabeled proteins in aqueous solution, and its application to the quantitation of protein gradients in a centrifuge tube continues. The equilibrium dissociation of the holoenzyme tryptophan synthase into monomeric alpha and dimeric beta subunits was studies via sedimentation equilibrium. A mechanistic model for the dependence of the osmotic pressure of serum albumin upon concentration and pH has been developed. A scaled particle theory for the thermodynamic behavior of a two dimensional fluid of hard convex particles has been developed. Computer programs for the analysis of sedimentation equilibrium of solutions of a single macrosolute have been extended to treat additional models.